Thoughts on offset boxes?

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Cozy_Home

New Member
Aug 22, 2021
8
Massachusetts
Hey all,

Thought I’d tap your collective genius. I recently had a Jotul C550 Rockland insert installed. The flue was off by about an inch so the installer used an offset box. I’ve heard other people say they’ve used them without issue, but I’m wondering if they can cause draft limitations (seems logically they would).

I get my fire nice and hot with a hefty bed of coals and plenty of fuel. I’ll even let it burn with the door cracked for an hour, but no matter what, when I close the door the fire eventually snuffs out, even with the draft control fully open.

Gotta be the offset box right?
 
How dry is your wood? Have you burned with a modern epa stove before?
 
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How dry is your wood? Have you burned with a modern epa stove before?
I have, although not an insert. The wood is pretty well seasoned I think. No hissing or bubbles coming out of the ends but maybe it’s not so dry? Not sure, but even with other stoves I’ve used when they get hot enough they seem to burn anything. Just doesn’t seem to be burning right.
 
Hey all,

Thought I’d tap your collective genius. I recently had a Jotul C550 Rockland insert installed. The flue was off by about an inch so the installer used an offset box. I’ve heard other people say they’ve used them without issue, but I’m wondering if they can cause draft limitations (seems logically they would).

I get my fire nice and hot with a hefty bed of coals and plenty of fuel. I’ll even let it burn with the door cracked for an hour, but no matter what, when I close the door the fire eventually snuffs out, even with the draft control fully open.

Gotta be the offset box right?
An offset box should be an absolute last resort because they do effect draft. How tall is the chimney?
 
"I think"
Yes but I think for a few reasons. As I mentioned before, no hissing or bubbles, but also because I got the wood through the same merchant a friend does and it’s always been nice and dry. Also, it has been burning great in a fire pit without issue. I know a fire pit isn’t a stove, but after having used stoves for quite some time, this draft just doesn’t seem right.
 
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If at all possible, an elbow (15 or 30º) should be used in lieu of an offset box. They are a headache.
 
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Here it is with the door cracked. Roaring. Then after five mins with the door closed (hard to see because of the reflection but basically just embers and no flame). Had a fire going for approx 4 hours so there is a good base and it’s plenty hot.
 
Many will suggest that you get a moisture merger and check on the center of a fresh split face at room temperature. I will agree if you are wanting this addressed proving that it’s not your wood leaves insufficient draft as the last option.

Was the offset used because of tight clearance or just to make it line up? If the latter is the case it could be a relatively simple fix.

From my reading offset boxes are recommended for 20’ and up of flue height.
 
Many will suggest that you get a moisture merger and check on the center of a fresh split face at room temperature. I will agree if you are wanting this addressed proving that it’s not your wood leaves insufficient draft as the last option.

Was the offset used because of tight clearance or just to make it line up? If the latter is the case it could be a relatively simple fix.

From my reading offset boxes are recommended for 20’ and up of flue height.
I believe the offset was used to make it line up. I’m definitely going to find a way to rule out the wet wood option.
 
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